code: def testRegisterDispatchableTypeError(self):
      with self.assertRaisesRegex(ValueError, "Expected a type object"):
          dispatch.register_dispatchable_type(3)
      with self.assertRaisesRegex(
          ValueError, "Type .* has already been registered"
      ):
          dispatch.register_dispatchable_type(
              ragged_tensor.RaggedTensor
          )
  
imports: import collections
  import numpy
  from tensorflow.python.framework import _pywrap_python_api_dispatcher
  from tensorflow.python.framework import constant_op
  from tensorflow.python.framework import tensor
  from tensorflow.python.framework import test_util
  from tensorflow.python.ops.ragged import ragged_factory_ops
  from tensorflow.python.ops.ragged import ragged_tensor
  from tensorflow.python.platform import googletest
label_desc: Use image node_id 6 for calling the PythonTypeCheckerTest obj's underlying member method code with example usage: obj.testRegisterDispatchableTypeError() without return types